Jeff, I would suspect it would cut its effectiveness significantly. Let me illustrate: The OEM glass tint is enough to "eat" 30-40 mA out of a 2.4W panel (120mA) and depending on angle of the solar panel vs the window glass and the light source (sun) the loss may be even higher. Obviously, tinting the rear window would not be a priority for me with a rear mounted solar panel in the wings. The front mounted SRS also make it less safe to mount the panels on the front dash. We could go with flexible or film-based panels but their power yields seem a bit low for my liking.